Improvement in processes of determining the grade of lubricating-oils



UNITED STATES PATENT OFFICE.

.HIRAMB. EVEREST, OF ROCHESTER, NEW YORK.

IMPROVEMENT IN PROCESSES F DETERMINING THE GRADE 0F LUBR|CATING0ILS. I

Specification forming part of Letters Patent No. 174,506, dated March 7,1876; application filed January 6, 1876.

To all whom it may concern:

Be it known that I, HIRAM B. EVEREST, Of the city of Rochester, in thecounty of Monroe and State of New York, have invented a new and usefulImprovement in the Art of Determining the Grade of Petroleum-Oils forLubricating and other Purposes; and I do hereby declare that thefollowing is a full, clear, and exact description of the same.

When crude petroleum is prepared for lubricating, 850., by distilling0E, by any known process, the lighter hydrocarbons, it has beencustomary to determine the condition or quality of the oil-in the stillby means of a hydrometer test, to show the gravity of the product whilethe process of reducing is going on.

To do this, samples are taken from time to timefrom the still andweighed to determine when the desired point in the manufacture isreached. The product when completed is put on themarket and designatedand sold by gravity test.

My invention consists in applying arfiretest to the samples taken fromthe still during the processof manufacture, and determining the grade ofthe reduced oil by such fire-test, and in putting the same on the marketwith such fire-test as its distinguishing feature.

To make the requisite fire-test of the reduced oils requires athermometer of Wide range, say from 200 to 600 Fahrenheit, for testingall grades of oil.

A chemists sand-bath, with a porcelain cup heated by a Bunsen burner, issufficient for heating the samples. It is done with the thermometersuspended in the liquid oil; or it may be tested in a plain iron dish,containing about one half pint of oil, placed over the charcoal fire ina tinkers pot, with the thermometer suspended in the oil. As the heatincreases the application of a lighted taper to within one-half inch ofthe surface of the oil will show, if constantly repeated,

when the oil has reached the point of ignition, which is usual about orabove the point of flashing and going out. The degree of heat at whichthe oil takes fire permanently, as indicated bythe thermometer, iscalled the fire-test. Example: Franklin crude petroleum of 32 gravityBaum, as produced from the wells, when reduced without burning togravity, stands 320 firetest; when reduced to 29 gravity, stands 370fire-test; 285 gravity, stands 425 firetest; 275 gravity, stands 525fire-test, or thereabout. a

It is comparatively easy to make reduced oils, varying only 10 infire-test, by the best processes. So it will be seen that, when de;sirable to do so, more difi'erent grades of reduced oils can bedefinitely fixed upon and determined by my method of manufacture thancan be so accurately made by the old method of gravity-test. Again, myprocess of determining quality or grade of reduced oils is moreapplicable to the various gravities of crude petroleum, when beingreduced,

than the old method of. gravity-test.

Example: A gravity crude oil reduced to 31 gravity would stand as high afire-test as a 32 gravity crude reduced to 30 gravity, and would aboutequal it in lubricating power.

My process or invention consists in making all reduced oils toafire-test regardless of gravity.

What I claim as my invention, and desire to secure by Letters Patent, is

The process of determining the grade of lubricating-oils, which consistsin applying the fire-test thereto during their man ufacture,

substantially as set forth.

In witness whereof I have hereunto signed my name in the presence of twosubscribing I witnesses.

HIRAM B. EVEREST.

Witnesses:

R. F. OSGOOD, E. B. SGOTT.

